Add support of ERC223

[maxnorm]

Implement the token fallback function to handle a more safe version of the ERC20 (ERC223).

This token remove the 2-step process of approve & pull from the contract. With the ERC223, the contract implement a function managing the reception of the tokens. This prevent lose of token if sending to contracts that doesn't support tokens.

Over 100 millions are lost due to this ERC20 inexistant transfer check. https://dexaran.github.io/erc20-losses/

https://ethereum.org/en/developers/docs/standards/tokens/erc-223/
https://github.com/Dexaran/ERC223-token-standard

[maxnorm]

A new interface would be needed to avoid overloading the interface of the ERC20.

It will also give more freedom to project that want to support it or not